Contact spring index system for timepieces

ABSTRACT

A contact spring index system for timepieces comprises a simplified indexing arrangement wherein an oscillating balance wheel activates a contact spring to directly drive the seconds wheel of the timepiece. More specifically, the drive means for the timepiece oscillates the balance wheel at a predetermined frequency while a contact pin mounted on the balance wheel periodically displaces a cantilevered contact spring. The displaced contact spring engages and drives a ratchet wheel in a predetermined manner. The ratchet wheel is mounted on a shaft which includes a worm gear portion in direct engagement with the seconds wheel of the timepiece. Thus, the balance wheel motion is directly transmitted by the contact spring to the timing wheels of the timepiece.

United States Patent 1191 Suard 1 Oct. 7, 1975 [54] CONTACT SPRING INDEXSYSTEM FOR 3,504,206 3/1970 Fritsch 58/116 R X TIMEPIECES. FOREIGNPATENTS OR APPLICATIONS [75] Inventor: Jean G. Suard, Besancon, France343,301 1 1960 Switzerland 58/116 R [73] Asslgnee: 22:? CorporatlonWaterbury Primary ExaminerGeorge H. Miller, Jr.

[22] Filed: Feb. 13,1975 [57] ABSTRACT [52] US. Cl. 58/28 B; 58/116 R[51] Int. Cl. G04C 3/04; G04B 15/00 [58] Field of Search.... 58/28 R, 28A, 28 B, 116 R,

58/116 M, 117, 118, 121 R, 121 M [56] References Cited UNITED STATESPATENTS 1,826,719 10/1931 Battagay 58/28 A 1,911,062 5/1933 Conrad 58/28A 2,531,966 11/1950 Berge 1. 58/28 A 2,572,989 10/1951 Contant et al58/28 A X 2,631,423 3/1953 Sullivan et al. 58/28 A 3,153,896 10/1964Smulski 58/28 A 3,286,457 11/1966 Ando 58/116 R A contact spring indexsystem for timepieces comprises a simplified indexing arrangementwherein an oscillating balance wheel activates a contact spring todirectly drive the seconds wheel of the timepiece. More specifically,the drive means for the timepiece oscillates the balance wheel at apredetermined frequency while a contact pin mounted on the balance wheelperiodically displaces a cantilevered contact spring. The displacedcontact spring engages and drives a ratchet wheel in a predeterminedmanner. The ratchet wheel is mounted on a shaft which includes a wormgear portion in direct engagement with the seconds wheel of thetimepiece. Thus, the balance wheel motion is directly transmitted by thecontact spring to the timing wheels of the timepiece.

7 Claims, 9 Drawing Figures US. Patent Oct. 7,1975 She et2 of2 3,910,028

CONTACT SPRING INDEX SYSTEM FOR TIMEPIECES BACKGROUND. OF THE-INVENTIONThe present invention relates to timepieces and particularly to animproved indexing system for electric timepieces.

The prior art includes various indexing systemsfor use in watches.Typical arrangements are disclosed in Stephenson US. Pat. .No. 40,508which issued Nov. 3, 1863 and Wensch US. Pat. No. 247,721 which issuedSept. 27, 1881 wherein displacement of a spring or lever by a balancewheel is utilized to drive an escapement mechanism.-

German OLS 1,673,770 dated Apr. 25, 1967 in the name of ManfredGrozinger disclosesan indexing apparatus wherein a tooth member affixedto one end of the watch stem forces a contact spring into engagementwith an index wheel for driving purposes. Further exemplary of the artis US. Pat. No. 1,772,556 to A. F. Poole which issued Aug. 12, 1930disclosing the use of a pawl and worm gear in an indexing device. Alsoof interest are US. Pat. No'. 2,976,673 to Petters et al which issuedMar. 28, 1961, US. Pat. No.'3,153,896 to Smulski which issued Oct. 27,1964 and US. Pat. No. 3,184,910 to Laviolette which issued May 25, 1965.These patents disclose various limited features in the indexing art andhave been cited herein as of general interest. The prior art mentionedabove is not intended to be an all inclusive listing of pertinent priorart patents but merely is intended to state the-more pertinent prior artwhich has come to applicants attention.

The present invention comprises an extremely simple and advantageousindexing mechanism which differs considerably from the prior artdiscussed above. In this invention, the seconds wheel is in directengagement with the worm gear portion of the ratchet shaft utilizingrelatively few and inexpensive parts to provide an extemely accuratetimepiece design.

SUMMARY THE INVENTION The present invention pertains to a contact springindex system for timepieces wherein a contact pin on an oscillatorbalance wheel activates a cantilevered contact spring to directly drivean indexing arrangement. In the preferred embodiment, an electric motorfor the timepiece drives the balance wheel at a predetermined frequency.A contact pin which projects outwardly from the balance wheel displacesthe free end of the contact spring preferably with a slight liftingmotion. The displaced contact spring indexes a ratchet wheel shaft whichdrives the seconds wheel of the timepiece via a worm gear portion onsaid shaft. The axis of the ratchet wheel may be off-centered withrespect to the balance wheel staff to impart added lift to the contactspring and thereby improve the functioning of the ratchet wheel.

Accordingly, an object of this invention is to provide a new andimproved indexing system for timepieces.

Another object of this invention is to provide a new and improvedcontact spring means for directly driving an indexing arrangement.

A more specific object of this invention is to provide a new andimproved indexing means for an electric timepiece wherein a contactspring is activated by an oscillating balance wheel to directly drive aratchet wheel coupled to the seconds wheel of the timepiece.

BRIEF DESCRIPTION or THE DRAWINGS Other objects and advantages of thisinvention may be seen from the following description when viewed inconjunction with the accompanying drawings wherein:

FIG. 1 is a simplified perspective view of the indexing systemcomprising the present invention with'conventional portions of thetimepiece omitted.

FIG. 2 is a partial top view of the indexing system of FIG. 1illustrating the relationship of the contact pin and contact spring ineffecting movement of the ratchet wheel.

FIG. 3a-3d illustrate sequentially and in a simplified manner thedriving of the ratchet wheel by the contact spring.

FIG. 4a and 4b illustrate the functioning of the ratchet wheel andcontact pin in somewhat greater detail; and

FIG. 5 illustrates the improved functioning of the system due to an'offcentered index wheel.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings, theinvention comprises an indexing system 10 for timepieces of the electricor electronic type. Since the invention is suitable for use withnumerous timepiece designs and the details of such timepieces areconventional and well-known, only the specific elements of the inventionare shown in the drawings. For example, the balance wheel 11 is mountedto staff 12 and includes a coil 13 mounted thereto. The balance wheel 11is oscillated back and forth about the staff axis by a drive means orcircuit (not shown) which interacts with the coil 13. The details ofsuch drive means being within the skill of the art are omitted from therepresentation of FIG. 1.

The balance wheel 11 includes a mounting or contact 14 having a contactpin 16 projecting downwardly therefrom. The pin 16 may be mounted forrotation or fixedly mounted so that it remains in place as it engagesthe free end 17 of the contact spring 18. The other end 19 of thecontact spring 18 is fixedly mounted in an insulated contact block '21so that the spring is cantilevered outwardly therefrom. The free end 17of the spring 18 is displaced by the contact pin 16 as the balance wheeloscillates back and forth in the manner shown in FIG. 4a.

A ratchet wheel 22 is mounted on the end of a shaft 23 which ispositioned substantially parallel to the contact spring 18. The shaft 23also includes an intermediate worm gear portion 24 which engages theseconds wheel 25 of the timepiece. The seconds wheel 25 is, of course,coupled to the minutes wheel and hour wheel of the timepiece in aconvenient manner so that the driving movement of the balance wheel 11is transmitted to the watch indicating means (not shown) via thedisclosed indexing arrangement.

In operation the contact pin 16 on the oscillatory balance wheel 11engages the end 17 of the contact spring 18 as shown in FIG. 3a. As thebalance wheel 13 oscillates in the direction of the arrow in FIG. 3b,the ratchet wheel is indexed thereby. FIG. 30 shows the end 17 of thecontact spring 18 at rest while FIG. 3d shows the return movement of thespring as the balance wheel 13 is oscillated in the opposite direction.

As shown in greater detail in FIG. 4a and 4b, the balance staff axis 26and the axis 28 of the ratchet wheel 22 are in substantially the sameplane. The contact improved tooth/spring working condition by reducingthe lifting of the contact spring 18 by the distance 31 during thereverse movement of the balance wheel 11 and as the spring end 17 clearsthe tooth 33. The distance 35 represents the lift up distance of thespring end 17 during the reverse movement of the balance wheel 11. Afterthe return movement, the spring 18 moves the wheel 22 in the indicateddirection as the balance wheel 11 moves forward. Thus the wheel 22 isdriven in a single direction.

As the ratchet wheel 22 is indexed by the contact spring 18, theintermediate worm gear portion 24 on the ratchet shaft drives themeshing seconds wheel 25 of the timepiece The seconds wheel 25 iscoupled to the other timing wheels in a conventional arrangement so thatthe indicating means are driven thereby. The indexing means 10 of thepresent invention thus permits asimple and inexpensive direct drive fromthe balance wheel 11 which is suitable for use in highly accuratetimepieces of the quartz crystal type.

While the invention has been explained by a detailed description ofcertain specific embodiments, it is understood that variousmodifications and substitutions can be made in any of them within thescope of the appended claims which are intended also to includeequivalents of such embodiments.

What is claimed is:

1. An indexing system for timepieces having a drive means coupled tosaid system comprising:v

an oscillatory member driven by said drive means and having contactmeans mounted thereon,

a contact spring fixedly mounted at one end and having the other freeend periodically engaged by the contact means during the movement of theoscillatory member,

a shaft rotatably mounted within the timepiece and adjacent the contactspring, said shaft having a worm gear portion and a ratchet wheelmounted to be engaged and driven by the contact spring, and

timing means engaging the worm gear portion of the shaft to be indexedthereby when the contact spring drives the ratchet wheel under urging ofthe contact means on the oscillatory member.

2. An indexing system for timepieces having a drive means coupled tosaid system in accordance with claim 1 wherein:

the oscillatory member comprises a balance wheel and the contact meanscomprises a pin extending outwardly from the balance wheel.

3. Anindexing system for timepieces having a drive means coupled to saidsystem in accordance with claim 1 wherein:

the contact spring is an elongated flexible member extendingsubstantially parallel to the shaft.

4. An indexing system for timepieces having a drive means coupled tosaid system in accordance with claim 1 wherein:

the timing means comprises a seconds wheel meshing with the worm gearportion of the shaft and being driven thereby, minutes and hours meansbeing coupled to said seconds wheel, and indicating means driven by therespective seconds wheel and minutes and hours means.

5. An indexing system for timepieces having a drive means coupled tosaid system in accordance with claim 1 wherein:

' the axis of the ratchet wheel is off centered with respect to the axisof the balance shaft to impart increased lift to the contact spring sothat it readily clears the ratchet wheel during its movement in areverse direction.

6. An indexing system for timepieces having a drive means coupled tosaid system in accordance with claim 1 wherein: V

g the contact pin is fixedly mounted adjacent the balance wheel and isdriven thereby. 7. An indexing system for timepieces having a drivemeans coupled to said system in accordance with claim 1 wherein:

the ratchet wheel includes a plurality of teeth which are designed sothat the teeth are engaged by the contact spring to be driven in onedirection.

1. An indexing system for timepieces having a drive means coupled tosaid system comprising: an oscillatory member driven by said drive meansand having contact means mounted thereon, a contact spring fixedlymounted at one end and having the other free end periodically engaged bythe contact means during the movement of the oscillatory member, a shaftrotatably mounted within the timepiece and adjacent the contact spring,said shaft having a worm gear portion and a ratchet wheel mounted to beengaged and driven by the contact spring, and timing means engaging theworm gear portion of the shaft to be indexed thereby when the contactspring drives the ratchet wheel under urging of the contact means on theoscillatory member.
 2. An indexing system for timepieces having a drivemeans coupled to said system in accordance with claim 1 wherein: theoscillatory member comprises a balance wheel and the contact meanscomprises a pin extending outwardly from the balance wheel.
 3. Anindexing system for timepieces having a drive means coupled to saidsystem in accordance with claim 1 wherein: the contact spring is anelongated flexible member extending substantially parallel to the shaft.4. An indexing system for timepieces having a drive means coupled tosaid system in accordance with claim 1 wherein: the timing meanscomprises a seconds wheel meshing with the worm gear portion of theshaft and being driven thereby, minutes and hours means being coupled tosaid seconds wheel, and indicating means driven by the respectiveseconds wheel and minutes and hours means.
 5. An indexing system fortimepieces having a drive means coupled to said system in accordancewith claim 1 wherein: the axis of the ratchet wheel is off centered withrespect to the axis of the balance shaft to impart increased lift to thecontact spring so that it readily clears the ratchet wheel during itsmovement in a reverse direction.
 6. An indexing system for timepieceshaving a drive means coupled to said system in accordaNce with claim 1wherein: the contact pin is fixedly mounted adjacent the balance wheeland is driven thereby.
 7. An indexing system for timepieces having adrive means coupled to said system in accordance with claim 1 wherein:the ratchet wheel includes a plurality of teeth which are designed sothat the teeth are engaged by the contact spring to be driven in onedirection.